KLOG.DLL C run-time usage

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The following C program is a simple example:

·

It loads KLOG.DLL at run-time. It assumes it is available in the same directory or in the system root directory

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It gets all functions exported by KLOG.DLL,

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It uses the functions to set parameters, and

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Finally, it sends a message to host 'sysloghost' port 2110, and reports any errors.

/*
  Send a syslog message using KLOG.DLL. This is the same as the command
  klog -h sysloghost -u 2110 -r myproc -p 122 –m "Local event occurred"
*/

#include <stdio.h>
#include <windows.h>

//DLL functions
FARPROC KLogInitialise;
FARPROC KLogSetPortByService;
FARPROC KLogSetPortByNum;
FARPROC KLogSetHostAddress;
FARPROC KLogSetMessagePriority;
FARPROC KLogSetMessageLevelNum;
FARPROC KLogSetMessageFacilityNum;
FARPROC KLogSetMessageLevelName;
FARPROC KLogSetMessageFacilityName;
FARPROC KLogSetProcessName;
FARPROC KLogUseTCP;
FARPROC KLogUseSilentErrors;
FARPROC KLogSetMessage;
FARPROC KLogSendMessage;
FARPROC KLogReturnError;
FARPROC KLogGetUsageHelp;
FARPROC KLogGetUsageExample;
FARPROC KLogGetSoftwareInfo;
FARPROC KLogGetPriorityNames;

void getAllFunctions(HMODULE);

int main()
{
  int  UdpPort = 2110;
  char Loghost[] = "sysloghost";
  int  Priority = 122;
  char Processname = "myproc";
  char Msg[] = "Local event occurred";

  int  Kret = 0;      // Returned error code
  char Kerror[100];   // Returned error message
  HMODULE KLib;       // DLL handle

  // Load library, hopefully in current directory.
  if ((KLib = LoadLibrary("klog.dll")) == NULL)
  {
    fprintf(stderr, "Cannot find klog.dll.\nCannot send messages.\n");
    return 1;
  }

  // Get all DLL functions
  getAllFunctions(KLib);

  // Send the message
  KLogInitialise();                         // Do defaults
  KLogSetPortByNum(UdpPort);                // Set destination port
  KLogSetHostAddress(Loghost);              // Set host
  KLogSetMessagePriority(Priority);         // Priority
  KLogSetProcessName(1, Processname);       // RFC process name
  KLogSetMessage(Msg);                      // Set message text

  // Send the message. If FALSE, then check Kret for a return code.
  // Use the DLL to get an error string. If silent errors is enabled,
  // no string is returned in Kerror.
  if (KLogSendMessage(&Kret) == FALSE)
  {
     KLogReturnError(Kerror, sizeof(Kerror));

     if (Kerror[0] != '\0')
        fprintf(stderr, "Error %d: %s\n", Kret, Kerror);

     return 1;
  }

  return 0;
}

/*
  Get all functions from the DLL.
*/

void getAllFunctions(HMODULE KLib)
{
  KLogInitialise = GetProcAddress(KLib, "KLogInitialise");
  KLogSetPortByService = GetProcAddress(KLib, "KLogSetPortByService");
  KLogSetPortByNum = GetProcAddress(KLib, "KLogSetPortByNum");
  KLogSetHostAddress = GetProcAddress(KLib, "KLogSetHostAddress");
  KLogSetMessagePriority = GetProcAddress(KLib, "KLogSetMessagePriority");
  KLogSetMessageLevelNum = GetProcAddress(KLib, "KLogSetMessageLevelNum");
  KLogSetMessageFacilityNum = GetProcAddress(KLib, "KLogSetMessageFacilityNum");
  KLogSetMessageLevelName = GetProcAddress(KLib, "KLogSetMessageLevelName");
  KLogSetMessageFacilityName = GetProcAddress(KLib, "KLogSetMessageFacilityName");
  KLogSetProcessName = GetProcAddress(KLib, "KLogSetProcessName");
  KLogUseTCP = GetProcAddress(KLib, "KLogUseTCP");
  KLogUseSilentErrors = GetProcAddress(KLib, "KLogUseSilentErrors");
  KLogSetMessage = GetProcAddress(KLib, "KLogSetMessage");
  KLogSendMessage = GetProcAddress(KLib, "KLogSendMessage");
  KLogReturnError = GetProcAddress(KLib, "KLogReturnError");
  KLogGetUsageHelp = GetProcAddress(KLib, "KLogGetUsageHelp");
  KLogGetUsageExample = GetProcAddress(KLib, "KLogGetUsageExample");
  KLogGetSoftwareInfo = GetProcAddress(KLib, "KLogGetSoftwareInfo");
  KLogGetPriorityNames = GetProcAddress(KLib, "KLogGetPriorityNames");
}